Update cssparser-macros to syn 2

This makes no effort to gracefully handle errors that the old code
didn't handle.

Author: glandium

macros/Cargo.toml

@@ -14,4 +14,4 @@ proc-macro = true
 
 [dependencies]
 quote = "1"
-syn = {version = "1", features = ["full", "extra-traits"]}
+syn = {version = "2", features = ["full", "extra-traits"]}

macros/lib.rs

@@ -38,14 +38,18 @@ pub fn _cssparser_internal_max_len(input: TokenStream) -> TokenStream {
     .into()
 }
 
+fn get_byte_from_lit(lit: &syn::Lit) -> u8 {
+    if let syn::Lit::Byte(ref byte) = *lit {
+        byte.value()
+    } else {
+        panic!("Found a pattern that wasn't a byte")
+    }
+}
+
 fn get_byte_from_expr_lit(expr: &syn::Expr) -> u8 {
     match *expr {
         syn::Expr::Lit(syn::ExprLit { ref lit, .. }) => {
-            if let syn::Lit::Byte(ref byte) = *lit {
-                byte.value()
-            } else {
-                panic!("Found a pattern that wasn't a byte")
-            }
+            get_byte_from_lit(lit)
         }
         _ => unreachable!(),
     }
@@ -59,15 +63,15 @@ fn parse_pat_to_table<'a>(
     table: &mut [u8; 256],
 ) {
     match pat {
-        &syn::Pat::Lit(syn::PatLit { ref expr, .. }) => {
-            let value = get_byte_from_expr_lit(expr);
+        &syn::Pat::Lit(syn::PatLit { ref lit, .. }) => {
+            let value = get_byte_from_lit(lit);
             if table[value as usize] == 0 {
                 table[value as usize] = case_id;
             }
         }
-        &syn::Pat::Range(syn::PatRange { ref lo, ref hi, .. }) => {
-            let lo = get_byte_from_expr_lit(lo);
-            let hi = get_byte_from_expr_lit(hi);
+        &syn::Pat::Range(syn::PatRange { ref start, ref end, .. }) => {
+            let lo = get_byte_from_expr_lit(&start.as_ref().unwrap());
+            let hi = get_byte_from_expr_lit(&end.as_ref().unwrap());
             for value in lo..hi {
                 if table[value as usize] == 0 {
                     table[value as usize] = case_id;